.TH "TESTING/EIG/dget51.f" 3 "Version 3.12.0" "LAPACK" \" -*- nroff -*- .ad l .nh .SH NAME TESTING/EIG/dget51.f .SH SYNOPSIS .br .PP .SS "Functions/Subroutines" .in +1c .ti -1c .RI "subroutine \fBdget51\fP (itype, n, a, lda, b, ldb, u, ldu, v, ldv, work, result)" .br .RI "\fBDGET51\fP " .in -1c .SH "Function/Subroutine Documentation" .PP .SS "subroutine dget51 (integer itype, integer n, double precision, dimension( lda, * ) a, integer lda, double precision, dimension( ldb, * ) b, integer ldb, double precision, dimension( ldu, * ) u, integer ldu, double precision, dimension( ldv, * ) v, integer ldv, double precision, dimension( * ) work, double precision result)" .PP \fBDGET51\fP .PP \fBPurpose:\fP .RS 4 .PP .nf !> !> DGET51 generally checks a decomposition of the form !> !> A = U B V' !> !> where ' means transpose and U and V are orthogonal\&. !> !> Specifically, if ITYPE=1 !> !> RESULT = | A - U B V' | / ( |A| n ulp ) !> !> If ITYPE=2, then: !> !> RESULT = | A - B | / ( |A| n ulp ) !> !> If ITYPE=3, then: !> !> RESULT = | I - UU' | / ( n ulp ) !> .fi .PP .RE .PP \fBParameters\fP .RS 4 \fIITYPE\fP .PP .nf !> ITYPE is INTEGER !> Specifies the type of tests to be performed\&. !> =1: RESULT = | A - U B V' | / ( |A| n ulp ) !> =2: RESULT = | A - B | / ( |A| n ulp ) !> =3: RESULT = | I - UU' | / ( n ulp ) !> .fi .PP .br \fIN\fP .PP .nf !> N is INTEGER !> The size of the matrix\&. If it is zero, DGET51 does nothing\&. !> It must be at least zero\&. !> .fi .PP .br \fIA\fP .PP .nf !> A is DOUBLE PRECISION array, dimension (LDA, N) !> The original (unfactored) matrix\&. !> .fi .PP .br \fILDA\fP .PP .nf !> LDA is INTEGER !> The leading dimension of A\&. It must be at least 1 !> and at least N\&. !> .fi .PP .br \fIB\fP .PP .nf !> B is DOUBLE PRECISION array, dimension (LDB, N) !> The factored matrix\&. !> .fi .PP .br \fILDB\fP .PP .nf !> LDB is INTEGER !> The leading dimension of B\&. It must be at least 1 !> and at least N\&. !> .fi .PP .br \fIU\fP .PP .nf !> U is DOUBLE PRECISION array, dimension (LDU, N) !> The orthogonal matrix on the left-hand side in the !> decomposition\&. !> Not referenced if ITYPE=2 !> .fi .PP .br \fILDU\fP .PP .nf !> LDU is INTEGER !> The leading dimension of U\&. LDU must be at least N and !> at least 1\&. !> .fi .PP .br \fIV\fP .PP .nf !> V is DOUBLE PRECISION array, dimension (LDV, N) !> The orthogonal matrix on the left-hand side in the !> decomposition\&. !> Not referenced if ITYPE=2 !> .fi .PP .br \fILDV\fP .PP .nf !> LDV is INTEGER !> The leading dimension of V\&. LDV must be at least N and !> at least 1\&. !> .fi .PP .br \fIWORK\fP .PP .nf !> WORK is DOUBLE PRECISION array, dimension (2*N**2) !> .fi .PP .br \fIRESULT\fP .PP .nf !> RESULT is DOUBLE PRECISION !> The values computed by the test specified by ITYPE\&. The !> value is currently limited to 1/ulp, to avoid overflow\&. !> Errors are flagged by RESULT=10/ulp\&. !> .fi .PP .RE .PP \fBAuthor\fP .RS 4 Univ\&. of Tennessee .PP Univ\&. of California Berkeley .PP Univ\&. of Colorado Denver .PP NAG Ltd\&. .RE .PP .PP Definition at line \fB147\fP of file \fBdget51\&.f\fP\&. .SH "Author" .PP Generated automatically by Doxygen for LAPACK from the source code\&.